I don't see any "throw a third carrier in for free" mentioned in that article.
The link says the savings from Newport would be $1.6B.
It also quotes the Navy acquisitions chief pointing out "about a third of the cost of a carrier comes from government-furnished equipment that the Navy would contract for separately" and that he previously said the overall savings of ordering two at once would be around $2.5B after considering similar efficiencies of "scale" from those vendors.
Considering the cost[1] of these Ford-class carriers is around $13B this represents a savings of about 10% overall, at least according to my crude, back-of-the-napkin math [ 2.5B/(2x13B) or 1.6B/(2/3x2x13B) ].
Congress, collectively, is not often referred to as "smart". If I'm a senator and a guy sitting in front of me makes that offer, I take him up on it and hold his feet to the fire. How do you explain that to your constituents? I was offered free, and I said no. Re-elect Me!!!
To be fair, the building of the actual carrier is just part of the price of a carrier. What's the cost to also fit that carrier out with all of the various aircraft required to make the carrier worth having? Didn't we see an example of this when the NSA donated Hubble equivalent satellites to NASA, but NASA had to politely say no since they had no budget to operate them?
> Didn't we see an example of this when the NSA donated Hubble equivalent satellites to NASA, but NASA had to politely say no since they had no budget to operate them?
It was the NRO not the NSA and NASA did accept the donation. They announced the mission schedule for one of the satellites in 2016 [1]